1. Field of the Invention
The invention relates to an electric pencil sharpener, more particularly to an electric pencil sharpener with an automatic stop feature.
2. Description of the Related Art
One type of conventional electric pencil sharpeners, such as those disclosed in US 2010/032658A1 and U.S. Pat. No. 7,455,087B2, is configured to automatically stop a pencil sharpening operation when a predetermined length of the tip portion of an inserted pencil has been sharpened. This type of electric pencil sharpener is typically provided with a single helical cutter or a single flat blade so as to provide a space for installing an auto-stop mechanism. However, this type of electric pencil sharpener typically suffers from balancing problems during the pencil sharpening operation, resulting in an unstable shaving quality.
Another type of conventional electric pencil sharpeners, such as those disclosed in U.S. Pat. No. 7,913,731B2 and US 2010/0326569A1, is provided with two helical cutters which are substantially equal in length to provide better balance. However, with the provision of the additional cutter, the electric pencil sharpener no longer has space for accommodating an auto-stop mechanism.